Accurate evaluation of disease levels in wild rice germplasm and identification of disease resistance are critical for developing rice varieties resistant to blast disease.However,existing evaluation methods face limi...Accurate evaluation of disease levels in wild rice germplasm and identification of disease resistance are critical for developing rice varieties resistant to blast disease.However,existing evaluation methods face limitations that hinder progress in breeding.To address these challenges,we proposed an AI-powered method for evaluating blast disease levels and identifying resistance in wild rice.A lightweight segmentation model for diseased leaves and lesions was developed,incorporating an improved federated learning approach to enhance robustness and adaptability.Based on the segmentation results and resistance identification technical specifications,wild rice materials were evaluated into 10 disease levels(L0 to L9),further enabling disease-resistance identification through multiple replicates of the same materials.The method was successfully implemented on augmented reality glasses for real-time,first-person evaluation.Additionally,high-speed scanners and edge computing devices were integrated to enable continuous,precise,and dynamic evaluation.Experimental results demonstrate the outstanding performance of the proposed method,achieving effective segmentation of diseased leaves and lesions with only 0.22 M parameters and 5.3 G floating-point operations per second(FLOPs),with a mean average precision(mAP@0.5)of 96.3%.The accuracy of disease level evaluation and disease-resistance identification reached 99.7%,with a practical test accuracy of 99.0%,successfully identifying three highly resistant wild rice materials.This method provides strong technical support for efficiently identifying wild rice materials resistant to blast disease and advancing resistance breeding efforts.展开更多
Sweet and sour are the most important taste of blueberries,and they are produced by sugar and acid,respectively.Their contributions to the taste depend not only on the levels of sugar and acid,but also on the types an...Sweet and sour are the most important taste of blueberries,and they are produced by sugar and acid,respectively.Their contributions to the taste depend not only on the levels of sugar and acid,but also on the types and relative proportions of sugar and acid.Therefore,it is very important to evaluate the composition and levels of sugar and acid in blueberries.Regional differences and variety diversity also affect the sugar and acid characteristics of fruits.Therefore,this study selected two main producing regions in northern China(Weihai and Yingkou)to examine the sugar and acid characteristics of 11 common blueberry cultivars.The indexes measured included soluble sugars,organic acids,soluble solid content and titratable acidity.The results showed that glucose and fructose were the major sugars,and citric acid and quinic acid were the major organic acids.Correlation analysis showed that glucose,fructose,and sucrose were positively correlated with total sugar content;the citric acid content was positively correlated with the titratable acidity and total organic acids.Titratable acidity,glucose,fructose,sucrose,total sugar content,citric acid,shikimic acid and total acid content of the blueberries varied significantly between regions(P<0.05).In general,compared with Weihai blueberries,Yingkou blueberries had higher sugar content and lower acid content.The results of this study may provide useful references for the evaluation of sweet and sour flavors and cultivar selection of blueberries.展开更多
The availability of many high-degree Global Geopotential Models(GGMs), namely EGM2008, EIGEN-6C4,GECO, SGG-UGM-1, SGG-UGM-2, XGM2019e_2159, and GGMPlus, challenges users regarding which model is best for Vietnam. This...The availability of many high-degree Global Geopotential Models(GGMs), namely EGM2008, EIGEN-6C4,GECO, SGG-UGM-1, SGG-UGM-2, XGM2019e_2159, and GGMPlus, challenges users regarding which model is best for Vietnam. This study, therefore, evaluates their performance by comparing them with GNSS/leveling data over Vietnam. Results show that their absolute and relative performances are largely independent of topographic conditions and geographical location and can be ranked into three classes:(1)XGM2019e_2159 has the highest accuracy,(2) the models EIGEN-6C4, GECO, SGG-UGM-1, SGG-UGM-2, and GGMPlus, have a very similar level of medium accuracy, while(3) EGM2008 is found to be the least accurate. In an absolute sense, the differences between GNSS/leveling and EGM2008-based height anomalies have a standard deviation(STD) of 0.290 ± 0.010 m, whereas, for XGM2019e_2159, this is 0.156 ± 0.006 m.All other models have STDs of(0.18-0.19) ± 0.007 m. Regarding relative performance without fitting, all GGMs have comparable accuracies for baseline length of 5-20 km, while for baselines longer than 20 km,the STD of XGM2019e_2159 is 1.5 ppm-0.5 ppm(approximately 19%-40%) lower compared with EGM2008, and 0.5 ppm-0.25 ppm(approximately 7%-36%) lower compared with EIGEN6C4, GECO,SGG-UGM-1, SGG-UGM-2, and GGMPlus. In addition, the STDs decrease significantly from 20 to 12 ppm in the range of 5-10 km, slightly from 12 to 6 ppm for 10-35 km, very slightly from 6 to 2.5 ppm for35-200 km, and then remain almost unchanged for longer baselines. After fitting, the relative accuracies of all GGMs are at the same level with negligible STD/RMSE values. Furthermore, only EGM2008 experiences significant regional differences, while other GGMs show more homogeneous spatial variation of absolute accuracy over Vietnam. These findings can contribute to the development of local quasigeoid models in Vietnam and may be helpful with the improvement of GGMs in the future.展开更多
Attitude references are greatly needed for the evaluation and calibration of Inertial Navigation Systems(INSs),which are widely used in gravimeter,marine,and aeronautical navigation.High-accuracy turntable,INS,and Glo...Attitude references are greatly needed for the evaluation and calibration of Inertial Navigation Systems(INSs),which are widely used in gravimeter,marine,and aeronautical navigation.High-accuracy turntable,INS,and Global Navigation Satellite System have been utilized to verify the performance of relatively low-accuracy INS.The accuracy requirement of the attitude reference continuously increases with the rapid improvement of inertial sensors and navigation algorithms.However,the cost of attitude determination system increases rapidly with the increase of attitude accuracy requirement.To solve this limitation,the integration of level meter,INS,and low-cost turntable is proposed to provide level attitude,such as roll and pitch.The turntable is utilized to rotate the INS.An integration model of the level meter and INS is built to estimate the level attitude and reduce the cost of the turntable.The proposed method successfully avoids the dependence on high-accuracy turntables.An observability degree analysis is conducted to improve the level atti-tude accuracy further.The simulation and turntable test results indicate that the proposed method can provide high-accuracy level attitude without high-accuracy INS or turntable and is applicable to error calibration and attitude evaluation of INS.展开更多
[Objectives]Hubei Province has a superior geographical location,and is located in the middle and lower reaches of the Yangtze River,with pleasant climate and abundant natural resources.It is an important province of p...[Objectives]Hubei Province has a superior geographical location,and is located in the middle and lower reaches of the Yangtze River,with pleasant climate and abundant natural resources.It is an important province of population,agriculture and resources in China.[Methods]Based on the data of Statistical Yearbook of Hubei 2018,the agricultural economic indicators of the cities and prefectures in Hubei Province were analyzed with principal component analysis method by using SPSS19.0.[Results]The comprehensive scores and rankings of the agricultural economic development level of the 17 cities and prefectures in Hubei Province were obtained.They were divided into four agricultural development levels.[Conclusions]According to the analysis results,corresponding policy recommendations were put forward to promote the development of agricultural economy in Hubei Province.展开更多
In order to accurately predict and control the aging process of dams, new information should be collected continuously to renew the quantitative evaluation of dam safety levels. Owing to the complex structural charact...In order to accurately predict and control the aging process of dams, new information should be collected continuously to renew the quantitative evaluation of dam safety levels. Owing to the complex structural characteristics of dams, it is quite difficult to predict the time-varying factors affecting their safety levels. It is not feasible to employ dynamic reliability indices to evaluate the actual safety levels of dams. Based on the relevant regulations for dam safety classification in China, a dynamic probability description of dam safety levels was developed. Using the Bayesian approach and effective information mining, as well as real-time information, this study achieved more rational evaluation and prediction of dam safety levels. With the Bayesian expression of discrete stochastic variables, the a priori probabilities of the dam safety levels determined by experts were combined wfth the likelihood probability of the real-time check information, and the probability information for the evaluation of dam safety levels was renewed. The probability index was then applied to dam rehabilitation decision-making. This method helps reduce the difficulty and uncertainty of the evaluation of dam safety levels and complies with the current safe decision-making regulations for dams in China. It also enhances the application of current risk analysis methods for dam safety levels.展开更多
Based on the data of modern agricultural development level in Huaibei area,this paper made a comprehensive evaluation on the modern agricultural development of 6 cities in Huaibei area by Analytic Hierarchy Process( A...Based on the data of modern agricultural development level in Huaibei area,this paper made a comprehensive evaluation on the modern agricultural development of 6 cities in Huaibei area by Analytic Hierarchy Process( AHP). It analyzed the development trend and difference in the level of agricultural input,the level of agricultural output,the level of rural social development and the level of agricultural ecological security. The study shows that the overall level of modern agricultural development in Huaibei area is rising in the past 6 years,with the highest increase in Suzhou City,followed by Huainan City and Huaibei City,and the other cities ranking in the middle. In view of the problems in the process of modern agricultural development in Huaibei area,it came up with recommendations,including strengthening the land consolidation,transfer of agricultural population,improving the rural education and controlling the agricultural pollution.展开更多
At present,there is still no unified standard for evaluation of agricultural insurance security level,especially in the quantitative evaluation. In order to explore a scientific and reasonable evaluation method for ag...At present,there is still no unified standard for evaluation of agricultural insurance security level,especially in the quantitative evaluation. In order to explore a scientific and reasonable evaluation method for agricultural insurance security level,this paper analyzed the current situation of evaluation methods of social insurance,endowment insurance and medical insurance,as well as the application of security index. It is expected to provide a certain reference for evaluation of agricultural insurance security level by the agricultural insurance security index.展开更多
Based on fully understanding the significance of farmer training,this paper builds the evaluation index system for farmer training satisfaction level. Then this paper employs the field survey data about Yichang and Ji...Based on fully understanding the significance of farmer training,this paper builds the evaluation index system for farmer training satisfaction level. Then this paper employs the field survey data about Yichang and Jingzhou in Hubei Province to evaluate the farmer training satisfaction level in Hubei Province. Results show that farmers have high level of satisfaction on agricultural training in Hubei Province,and the average satisfaction level reaches 0. 8556; there are regional differences in the farmer training satisfaction level in Hubei Province; the index weight is not entirely directly proportional to the training satisfaction level in the evaluation index system. Finally,from training courses,training teachers,training organization and follow-up services,this paper brings forward the recommendations for improving farmer training satisfaction level in Hubei Province,improve farmer training system,further improve the effectiveness of training and promote farmers' quality.展开更多
Terrain slope and climate zone(heat zone)are important factors affecting land use zoning and agricultural production layout in mountainous areas.Using"weight grade method",a quantitative index of comprehensi...Terrain slope and climate zone(heat zone)are important factors affecting land use zoning and agricultural production layout in mountainous areas.Using"weight grade method",a quantitative index of comprehensively evaluating terrain slope and climatic(thermal)conditions in mountainous areas was proposed:terrain-climate superiority degree(TCSD),and TCSD,terrain superiority degree(TSD),and climate superiority degree(CSD)in 129 counties(cities and districts)of Yunnan Province were measured and analyzed.The results showed that TCSD in 50.39%of counties of Yunnan Province was relatively better(levels I and II),and TCSD in 38.76%of counties was moderate(level III),while TCSD in 10.85%of counties was relatively poorer(levels IV and V).展开更多
For a long time,Chinese construction industry has had disadvantages such as waste of resources,environmental pollution,long construction period,great influence by weather,low enterprise efficiency and poor benefit.Whi...For a long time,Chinese construction industry has had disadvantages such as waste of resources,environmental pollution,long construction period,great influence by weather,low enterprise efficiency and poor benefit.While being able to solve the disadvantages of traditional buildings,prefabricated buildings,as an important starting point to achieve the carbon peaking and carbon neutrality goals,are far superior to traditional buildings in green and low-carbon,energy conservation and emission reduction,which can accelerate the transformation and upgrading of the construction industry.In recent years,the government has vigorously promoted prefabricated buildings,but the implementation of prefabricated buildings has been frequently hindered and the development of prefabricated buildings in China has not achieve the expected goal in many aspects.Under the high-quality development strategy proposed by the central government,how to promote the high-quality development of prefabricated buildings in China is one of the key difficulties of Chinese construction industry in the future.Therefore,it is necessary to proceed from the connotation of the high-quality development of prefabricated buildings,establish an evaluation model for the high-quality development level of prefabricated buildings through AHP and comprehensive fuzzy evaluation to master the high-quality development level of prefabricated buildings in China,and explore the reasonable paths selection forthe high-quality development of prefabricated buildings in China.展开更多
A hundred and twenty-one households in Yujiang county, Jiangxi province were investigated by adopting questionnaire method, and the evaluation system of index was established according to the integrative, hierarchical...A hundred and twenty-one households in Yujiang county, Jiangxi province were investigated by adopting questionnaire method, and the evaluation system of index was established according to the integrative, hierarchical, scientific, practical, comparative and dynamic principles. The investigation data were firstly standardized and then processed with SPSS software. The index weight was confirmed by principal component analysis. Finally, the evaluation scale of ecoagriculture was calculated. The results showed that the evaluation value ranged from 0.141 to 0.689 for 121 households. Agricultural status of 113 households got the primary phase of ecoagriculture which accounting for 93.38%; 7 households into the second phase, representing 5.79% and only 1 household into the third phase according to the evaluation value. However, the ecoagriculture was divided into 5 stages, according to the evaluation value. Therefore, the ecoagriculture has huge potential to develop in red soil area, China.展开更多
Based on the specific situation of Hu’nan Province, this paper formulates an evaluation index system of agricultural informatization, and uses the comprehensive index method to analyze and evaluate the level of agric...Based on the specific situation of Hu’nan Province, this paper formulates an evaluation index system of agricultural informatization, and uses the comprehensive index method to analyze and evaluate the level of agricultural informatization in Hu’nan Province. The overall process of the comprehensive index method is that firstly, a set of index system for evaluation should be formulated, then the data of each index should be standardized, and finally the comprehensive index value should be calculated through weighted summation. Based on the established index evaluation system and model, this paper analyzes and evaluates the development of agricultural informatization in Hu’nan Province by using the ten-year index raw data of 14 cities in Hu’nan from 2010 to 2019.展开更多
Given the substantially increasing complexity of embedded systems, the use of relatively detailed clock cycle-accurate simulators for the design-space exploration is impractical in the early design stages. Raising the...Given the substantially increasing complexity of embedded systems, the use of relatively detailed clock cycle-accurate simulators for the design-space exploration is impractical in the early design stages. Raising the abstraction level is nowadays widely seen as a solution to bridge the gap between the increasing system complexity and the low design productivity. For this, several system-level design tools and methodologies have been introduced to efficiently explore the design space of heterogeneous signal processing systems. In this paper, we demonstrate the effectiveness and the flexibility of the Sesame/Artemis system-level modeling and simulation methodology for efficient peformance evaluation and rapid architectural exploration of the increasing complexity heterogeneous embedded media systems. For this purpose, we have selected a system level design of a very high complexity media application;a H.264/AVC (Advanced Video Codec) video encoder. The encoding performances will be evaluated using system-level simulations targeting multiple heterogeneous multiprocessors platforms.展开更多
To implement a quantificational evaluation for mechanical kinematic scheme more effectively,a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly,the structure ...To implement a quantificational evaluation for mechanical kinematic scheme more effectively,a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly,the structure of evaluation model is constructed according to evaluation indicator system. Then evaluation samples are generated and provided to train this model. Thus it can reflect the relation between attributive value and evaluation result,as well as the weight of evaluation indicator. Once evaluation indicators of each candidate are fuzzily quantified and fed into the trained network model,the corresponding evaluation result is outputted and the best alternative can be selected. Under this model,expert knowledge can be effectively acquired and expressed,and the quantificational evaluation can be implemented for kinematic scheme with multi-level evaluation indicator system. Several key problems on this model are discussed and an illustration has demonstrated that this model is feasible and can be regarded as a new idea for solving kinematic scheme evaluation.展开更多
According to basic connotation and design principles of ecocity, a comparatively integrated index system is constructed in the paper. And at the same time using hierarchy grey comprehensive evaluation method, a hierar...According to basic connotation and design principles of ecocity, a comparatively integrated index system is constructed in the paper. And at the same time using hierarchy grey comprehensive evaluation method, a hierarchy grey comprehensive evaluation model of ecocity is established, then on the basis of the model, a comprehensive evaluation support system is developed, and the theoretical guidance supplied for construction of ecocity is provided.展开更多
Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis （e...Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis （e. g. the pushover analysis）, and the structural damage is considered via plastic hinges. Simultaneously, a practical approach is developed to obtain the relationships between the proposed index and earthquake intensities based on the capacity spectrum method. The proposed index is then illustrated through two low-rise reinforced concrete frames, and it is also compared with some other indices. The results indicate that the proposed index is on the safe side and not sensitive to the lateral load pattern. The storey index is helpful to reflect the storey damage and to uncover the position of the weak storey. Finally, the relationship between performance levels and damage index values is also proposed through statistical analysis for the performance-based seismic evaluation.展开更多
This paper, based on the analysis and calculation of the groundwater resources in an arid region from 1980 to 2001, put forward the concept of ecological groundwater level threshold for either salinity control or the ...This paper, based on the analysis and calculation of the groundwater resources in an arid region from 1980 to 2001, put forward the concept of ecological groundwater level threshold for either salinity control or the determination of ecological warning. The surveys suggest that soil moisture and soil salinity are the most important environmental factors in determining the distribution and changes in vegetation. The groundwater level threshold of ecological warning can be determined by using a network of groundwater depth observation sites that monitor the environmental moisture gradient as reflected by plant physiological characteristics. According to long-term field observations within the Ejin oases, the groundwater level threshold for salinity control varied between 0.5 m and 1.5 m, and the ecological warning threshold varied between 3.5 m and 4.0 m. The quantity of groundwater re- sources （renewable water resources, ecological water resources, and exploitable water resources） in arid areas can be calculated from regional groundwater level information, without localized hydrogeological data. The concept of groundwater level threshold of ecological warning was established according to water development and water re- sources supply, and available groundwater resources were calculated. The concept not only enriches and broadens the content of groundwater studies, but also helps in predicting the prospects for water resources development.展开更多
There are many uncertain factors,such as stochastic,fuzzy and gray information in the risk analysis on natural hazard.The set pair analysis(SPA)deals effectively with the various uncertain factors contributing to eval...There are many uncertain factors,such as stochastic,fuzzy and gray information in the risk analysis on natural hazard.The set pair analysis(SPA)deals effectively with the various uncertain factors contributing to evaluation of the risk level of natural disasters.The evaluation indicators and standards of natural disasters risk are analyzed by identity-discrepancycontrary(IDC).The result,the connection numbers,still has uncertainty information.Thus,yielding the risk evaluation model of natural disasters based on connection function,which construct a set pair relation between the indicators of connection numbers and comprehensive evaluation standards,and describe uncertainty of the connection numbers by using connection function.The study showed that the proposed model takes into account only the uncertainty of risk evaluation indicator identification on natural disasters,also the uncertainty of result connection numbers.This approach gives full consideration to the uncertainty of systematic evaluation process along with the actual meaning of comprehensive evaluation functions.Therefore,this means it is able to reduce the uncertainty of final evaluation results and improve the accuracy and reasonability of evaluation results.This model is capable of reflecting actual situation of the risk evaluation on natural disaster affected by various uncertain factors and has a promotional value in the natural disaster risk assessment.展开更多
The satellite pseudo-range fault detection with the Receiver Autonomous Integrity Monitoring(RAIM)method is affected by several satellite observations and the geometric distribution of satellites.The poor geometry dis...The satellite pseudo-range fault detection with the Receiver Autonomous Integrity Monitoring(RAIM)method is affected by several satellite observations and the geometric distribution of satellites.The poor geometry distribution of satellites will conceal the positioning errorcaused by the satellite pseudo-range fault,resulting in unreliable detection results.Therefore,the availability evaluation must be made before RAIM to ensure that the fault detection performance will not be affected.On June 23,2020,China successfully launched the 30 th(last)navigation satellite of BeiDou’s third-generation navigation satellite system(BDS-3),which is also the 55 th BeiDou navigation satellite.Combining all the available satellites of BDS-1,BDS-2 and BDS-3,the positioning performance of BDS can be greatly improved.In order to evaluate the RAIM availability of BeiDou Navigation Satellite System(BDS)and Global Positioning System(GPS)in China,this paper first deduces the mathematical models and their characteristics of the three RAIM availability evaluation methods.Then,the study area(N10°-70°,E60°-150°)is divided into 4536 grid points at intervals of 1°×1°in latitude and longitude,and the elevations of these grid points are taken from the global terrain data file.The Horizontal Protection Level(HPL)values of these grid points are calculated during 8-15 June 2020 using BDS and GPS ephemeris data.The RAIM availability differences between the two systems are compared and analysed.The analysis shows the Horizontal Protection Level method(HPLM)based on single-satellite pseudo-range fault is the most practical and convenient.During the 8-day observation period,the HPL values of BDS are significantly smaller than those of GPS in terms of geographic location and observation time,and the variation of HPL time series of BDS is also smaller than that of GPS,which indicates that the RAIM availability of GPS in China is not as good as that of BDS.Most importantly,in the four flight stages of the aircraft’s Oceanic/Continental lowdensity En-route,Continental En-route,Terminal En-route and Non-precision approach(NPA),BDS can completely satisfy its RAIM availability requirement,while GPS can only meet the availability requirement of the En-route(Oceanic/Continental low density)phase,and the availability of the other three phases can at least reach 99.714%.展开更多
基金supported by the National Key Research and Development Program of China(Grant Nos.2022YFF0711805,2022YFF0711801,and 2021YFF0704204)the Project of Sanya Yazhou Bay Science and Technology City,China(Grant No.SCKJ-JYRC-2023-45)+3 种基金the National Natural Science Foundation of China(Grant Nos.31971792 and 32160421)the Innovation Project of the Chinese Academy of Agricultural Sciences(CAAS)(Grant Nos.CAAS-ASTIP-2024-AII and ZDXM23011)the Special Fund of Chinese Central Government for Basic Scientific Research Operations in Commonweal Research Institutes(Grant No.JBYW-AII-2024-05)the Nanfan Special Project,CAAS,China(Grant No.YBXM2312).
文摘Accurate evaluation of disease levels in wild rice germplasm and identification of disease resistance are critical for developing rice varieties resistant to blast disease.However,existing evaluation methods face limitations that hinder progress in breeding.To address these challenges,we proposed an AI-powered method for evaluating blast disease levels and identifying resistance in wild rice.A lightweight segmentation model for diseased leaves and lesions was developed,incorporating an improved federated learning approach to enhance robustness and adaptability.Based on the segmentation results and resistance identification technical specifications,wild rice materials were evaluated into 10 disease levels(L0 to L9),further enabling disease-resistance identification through multiple replicates of the same materials.The method was successfully implemented on augmented reality glasses for real-time,first-person evaluation.Additionally,high-speed scanners and edge computing devices were integrated to enable continuous,precise,and dynamic evaluation.Experimental results demonstrate the outstanding performance of the proposed method,achieving effective segmentation of diseased leaves and lesions with only 0.22 M parameters and 5.3 G floating-point operations per second(FLOPs),with a mean average precision(mAP@0.5)of 96.3%.The accuracy of disease level evaluation and disease-resistance identification reached 99.7%,with a practical test accuracy of 99.0%,successfully identifying three highly resistant wild rice materials.This method provides strong technical support for efficiently identifying wild rice materials resistant to blast disease and advancing resistance breeding efforts.
基金This research was supported by theAgricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2018-RIP-O7).
文摘Sweet and sour are the most important taste of blueberries,and they are produced by sugar and acid,respectively.Their contributions to the taste depend not only on the levels of sugar and acid,but also on the types and relative proportions of sugar and acid.Therefore,it is very important to evaluate the composition and levels of sugar and acid in blueberries.Regional differences and variety diversity also affect the sugar and acid characteristics of fruits.Therefore,this study selected two main producing regions in northern China(Weihai and Yingkou)to examine the sugar and acid characteristics of 11 common blueberry cultivars.The indexes measured included soluble sugars,organic acids,soluble solid content and titratable acidity.The results showed that glucose and fructose were the major sugars,and citric acid and quinic acid were the major organic acids.Correlation analysis showed that glucose,fructose,and sucrose were positively correlated with total sugar content;the citric acid content was positively correlated with the titratable acidity and total organic acids.Titratable acidity,glucose,fructose,sucrose,total sugar content,citric acid,shikimic acid and total acid content of the blueberries varied significantly between regions(P<0.05).In general,compared with Weihai blueberries,Yingkou blueberries had higher sugar content and lower acid content.The results of this study may provide useful references for the evaluation of sweet and sour flavors and cultivar selection of blueberries.
文摘The availability of many high-degree Global Geopotential Models(GGMs), namely EGM2008, EIGEN-6C4,GECO, SGG-UGM-1, SGG-UGM-2, XGM2019e_2159, and GGMPlus, challenges users regarding which model is best for Vietnam. This study, therefore, evaluates their performance by comparing them with GNSS/leveling data over Vietnam. Results show that their absolute and relative performances are largely independent of topographic conditions and geographical location and can be ranked into three classes:(1)XGM2019e_2159 has the highest accuracy,(2) the models EIGEN-6C4, GECO, SGG-UGM-1, SGG-UGM-2, and GGMPlus, have a very similar level of medium accuracy, while(3) EGM2008 is found to be the least accurate. In an absolute sense, the differences between GNSS/leveling and EGM2008-based height anomalies have a standard deviation(STD) of 0.290 ± 0.010 m, whereas, for XGM2019e_2159, this is 0.156 ± 0.006 m.All other models have STDs of(0.18-0.19) ± 0.007 m. Regarding relative performance without fitting, all GGMs have comparable accuracies for baseline length of 5-20 km, while for baselines longer than 20 km,the STD of XGM2019e_2159 is 1.5 ppm-0.5 ppm(approximately 19%-40%) lower compared with EGM2008, and 0.5 ppm-0.25 ppm(approximately 7%-36%) lower compared with EIGEN6C4, GECO,SGG-UGM-1, SGG-UGM-2, and GGMPlus. In addition, the STDs decrease significantly from 20 to 12 ppm in the range of 5-10 km, slightly from 12 to 6 ppm for 10-35 km, very slightly from 6 to 2.5 ppm for35-200 km, and then remain almost unchanged for longer baselines. After fitting, the relative accuracies of all GGMs are at the same level with negligible STD/RMSE values. Furthermore, only EGM2008 experiences significant regional differences, while other GGMs show more homogeneous spatial variation of absolute accuracy over Vietnam. These findings can contribute to the development of local quasigeoid models in Vietnam and may be helpful with the improvement of GGMs in the future.
基金supported by the National Natural Science Foundation of China(No.62073184).
文摘Attitude references are greatly needed for the evaluation and calibration of Inertial Navigation Systems(INSs),which are widely used in gravimeter,marine,and aeronautical navigation.High-accuracy turntable,INS,and Global Navigation Satellite System have been utilized to verify the performance of relatively low-accuracy INS.The accuracy requirement of the attitude reference continuously increases with the rapid improvement of inertial sensors and navigation algorithms.However,the cost of attitude determination system increases rapidly with the increase of attitude accuracy requirement.To solve this limitation,the integration of level meter,INS,and low-cost turntable is proposed to provide level attitude,such as roll and pitch.The turntable is utilized to rotate the INS.An integration model of the level meter and INS is built to estimate the level attitude and reduce the cost of the turntable.The proposed method successfully avoids the dependence on high-accuracy turntables.An observability degree analysis is conducted to improve the level atti-tude accuracy further.The simulation and turntable test results indicate that the proposed method can provide high-accuracy level attitude without high-accuracy INS or turntable and is applicable to error calibration and attitude evaluation of INS.
文摘[Objectives]Hubei Province has a superior geographical location,and is located in the middle and lower reaches of the Yangtze River,with pleasant climate and abundant natural resources.It is an important province of population,agriculture and resources in China.[Methods]Based on the data of Statistical Yearbook of Hubei 2018,the agricultural economic indicators of the cities and prefectures in Hubei Province were analyzed with principal component analysis method by using SPSS19.0.[Results]The comprehensive scores and rankings of the agricultural economic development level of the 17 cities and prefectures in Hubei Province were obtained.They were divided into four agricultural development levels.[Conclusions]According to the analysis results,corresponding policy recommendations were put forward to promote the development of agricultural economy in Hubei Province.
基金supported by the National Science and Technology Support Program of China (Program for the Eleventh Five-Year Plan, Grant No. 2006BAC14B03 and 2006BAC05B03)the National Natural Science Foundation of China (Grant No. 50679043)
文摘In order to accurately predict and control the aging process of dams, new information should be collected continuously to renew the quantitative evaluation of dam safety levels. Owing to the complex structural characteristics of dams, it is quite difficult to predict the time-varying factors affecting their safety levels. It is not feasible to employ dynamic reliability indices to evaluate the actual safety levels of dams. Based on the relevant regulations for dam safety classification in China, a dynamic probability description of dam safety levels was developed. Using the Bayesian approach and effective information mining, as well as real-time information, this study achieved more rational evaluation and prediction of dam safety levels. With the Bayesian expression of discrete stochastic variables, the a priori probabilities of the dam safety levels determined by experts were combined wfth the likelihood probability of the real-time check information, and the probability information for the evaluation of dam safety levels was renewed. The probability index was then applied to dam rehabilitation decision-making. This method helps reduce the difficulty and uncertainty of the evaluation of dam safety levels and complies with the current safe decision-making regulations for dams in China. It also enhances the application of current risk analysis methods for dam safety levels.
文摘Based on the data of modern agricultural development level in Huaibei area,this paper made a comprehensive evaluation on the modern agricultural development of 6 cities in Huaibei area by Analytic Hierarchy Process( AHP). It analyzed the development trend and difference in the level of agricultural input,the level of agricultural output,the level of rural social development and the level of agricultural ecological security. The study shows that the overall level of modern agricultural development in Huaibei area is rising in the past 6 years,with the highest increase in Suzhou City,followed by Huainan City and Huaibei City,and the other cities ranking in the middle. In view of the problems in the process of modern agricultural development in Huaibei area,it came up with recommendations,including strengthening the land consolidation,transfer of agricultural population,improving the rural education and controlling the agricultural pollution.
基金Supported by the National Science and Technology Project in the Twelfth FiveYear Plan Period(2014BALO7B03.2)
文摘At present,there is still no unified standard for evaluation of agricultural insurance security level,especially in the quantitative evaluation. In order to explore a scientific and reasonable evaluation method for agricultural insurance security level,this paper analyzed the current situation of evaluation methods of social insurance,endowment insurance and medical insurance,as well as the application of security index. It is expected to provide a certain reference for evaluation of agricultural insurance security level by the agricultural insurance security index.
基金Supported by Graduate Education Innovation Program of Zhongnan University of Economics and Law(2016Y1054)
文摘Based on fully understanding the significance of farmer training,this paper builds the evaluation index system for farmer training satisfaction level. Then this paper employs the field survey data about Yichang and Jingzhou in Hubei Province to evaluate the farmer training satisfaction level in Hubei Province. Results show that farmers have high level of satisfaction on agricultural training in Hubei Province,and the average satisfaction level reaches 0. 8556; there are regional differences in the farmer training satisfaction level in Hubei Province; the index weight is not entirely directly proportional to the training satisfaction level in the evaluation index system. Finally,from training courses,training teachers,training organization and follow-up services,this paper brings forward the recommendations for improving farmer training satisfaction level in Hubei Province,improve farmer training system,further improve the effectiveness of training and promote farmers' quality.
基金Graduate Program from Science Research Fund of Yunnan Department of Education(2021Y547).
文摘Terrain slope and climate zone(heat zone)are important factors affecting land use zoning and agricultural production layout in mountainous areas.Using"weight grade method",a quantitative index of comprehensively evaluating terrain slope and climatic(thermal)conditions in mountainous areas was proposed:terrain-climate superiority degree(TCSD),and TCSD,terrain superiority degree(TSD),and climate superiority degree(CSD)in 129 counties(cities and districts)of Yunnan Province were measured and analyzed.The results showed that TCSD in 50.39%of counties of Yunnan Province was relatively better(levels I and II),and TCSD in 38.76%of counties was moderate(level III),while TCSD in 10.85%of counties was relatively poorer(levels IV and V).
文摘For a long time,Chinese construction industry has had disadvantages such as waste of resources,environmental pollution,long construction period,great influence by weather,low enterprise efficiency and poor benefit.While being able to solve the disadvantages of traditional buildings,prefabricated buildings,as an important starting point to achieve the carbon peaking and carbon neutrality goals,are far superior to traditional buildings in green and low-carbon,energy conservation and emission reduction,which can accelerate the transformation and upgrading of the construction industry.In recent years,the government has vigorously promoted prefabricated buildings,but the implementation of prefabricated buildings has been frequently hindered and the development of prefabricated buildings in China has not achieve the expected goal in many aspects.Under the high-quality development strategy proposed by the central government,how to promote the high-quality development of prefabricated buildings in China is one of the key difficulties of Chinese construction industry in the future.Therefore,it is necessary to proceed from the connotation of the high-quality development of prefabricated buildings,establish an evaluation model for the high-quality development level of prefabricated buildings through AHP and comprehensive fuzzy evaluation to master the high-quality development level of prefabricated buildings in China,and explore the reasonable paths selection forthe high-quality development of prefabricated buildings in China.
文摘A hundred and twenty-one households in Yujiang county, Jiangxi province were investigated by adopting questionnaire method, and the evaluation system of index was established according to the integrative, hierarchical, scientific, practical, comparative and dynamic principles. The investigation data were firstly standardized and then processed with SPSS software. The index weight was confirmed by principal component analysis. Finally, the evaluation scale of ecoagriculture was calculated. The results showed that the evaluation value ranged from 0.141 to 0.689 for 121 households. Agricultural status of 113 households got the primary phase of ecoagriculture which accounting for 93.38%; 7 households into the second phase, representing 5.79% and only 1 household into the third phase according to the evaluation value. However, the ecoagriculture was divided into 5 stages, according to the evaluation value. Therefore, the ecoagriculture has huge potential to develop in red soil area, China.
文摘Based on the specific situation of Hu’nan Province, this paper formulates an evaluation index system of agricultural informatization, and uses the comprehensive index method to analyze and evaluate the level of agricultural informatization in Hu’nan Province. The overall process of the comprehensive index method is that firstly, a set of index system for evaluation should be formulated, then the data of each index should be standardized, and finally the comprehensive index value should be calculated through weighted summation. Based on the established index evaluation system and model, this paper analyzes and evaluates the development of agricultural informatization in Hu’nan Province by using the ten-year index raw data of 14 cities in Hu’nan from 2010 to 2019.
文摘Given the substantially increasing complexity of embedded systems, the use of relatively detailed clock cycle-accurate simulators for the design-space exploration is impractical in the early design stages. Raising the abstraction level is nowadays widely seen as a solution to bridge the gap between the increasing system complexity and the low design productivity. For this, several system-level design tools and methodologies have been introduced to efficiently explore the design space of heterogeneous signal processing systems. In this paper, we demonstrate the effectiveness and the flexibility of the Sesame/Artemis system-level modeling and simulation methodology for efficient peformance evaluation and rapid architectural exploration of the increasing complexity heterogeneous embedded media systems. For this purpose, we have selected a system level design of a very high complexity media application;a H.264/AVC (Advanced Video Codec) video encoder. The encoding performances will be evaluated using system-level simulations targeting multiple heterogeneous multiprocessors platforms.
基金Supported by the Shanxi Natural Science Foundation under contract number 20041070 and Natural Science Foundation of north u-niversity of China .
文摘To implement a quantificational evaluation for mechanical kinematic scheme more effectively,a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly,the structure of evaluation model is constructed according to evaluation indicator system. Then evaluation samples are generated and provided to train this model. Thus it can reflect the relation between attributive value and evaluation result,as well as the weight of evaluation indicator. Once evaluation indicators of each candidate are fuzzily quantified and fed into the trained network model,the corresponding evaluation result is outputted and the best alternative can be selected. Under this model,expert knowledge can be effectively acquired and expressed,and the quantificational evaluation can be implemented for kinematic scheme with multi-level evaluation indicator system. Several key problems on this model are discussed and an illustration has demonstrated that this model is feasible and can be regarded as a new idea for solving kinematic scheme evaluation.
文摘According to basic connotation and design principles of ecocity, a comparatively integrated index system is constructed in the paper. And at the same time using hierarchy grey comprehensive evaluation method, a hierarchy grey comprehensive evaluation model of ecocity is established, then on the basis of the model, a comprehensive evaluation support system is developed, and the theoretical guidance supplied for construction of ecocity is provided.
基金The National Basic Research Program of China(973 Program)(No.2007CB714200)
文摘Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis （e. g. the pushover analysis）, and the structural damage is considered via plastic hinges. Simultaneously, a practical approach is developed to obtain the relationships between the proposed index and earthquake intensities based on the capacity spectrum method. The proposed index is then illustrated through two low-rise reinforced concrete frames, and it is also compared with some other indices. The results indicate that the proposed index is on the safe side and not sensitive to the lateral load pattern. The storey index is helpful to reflect the storey damage and to uncover the position of the weak storey. Finally, the relationship between performance levels and damage index values is also proposed through statistical analysis for the performance-based seismic evaluation.
基金funded by the National Natural Science Foundation of China(9102500230970492)+2 种基金the Fundamental Research Funds for the Central Universities(GK201101002)the Key Project of the Chinese Academy of Sciences(KZZDEW-04-05)the National Key Technology R & D Program(2012BAC08B05)
文摘This paper, based on the analysis and calculation of the groundwater resources in an arid region from 1980 to 2001, put forward the concept of ecological groundwater level threshold for either salinity control or the determination of ecological warning. The surveys suggest that soil moisture and soil salinity are the most important environmental factors in determining the distribution and changes in vegetation. The groundwater level threshold of ecological warning can be determined by using a network of groundwater depth observation sites that monitor the environmental moisture gradient as reflected by plant physiological characteristics. According to long-term field observations within the Ejin oases, the groundwater level threshold for salinity control varied between 0.5 m and 1.5 m, and the ecological warning threshold varied between 3.5 m and 4.0 m. The quantity of groundwater re- sources （renewable water resources, ecological water resources, and exploitable water resources） in arid areas can be calculated from regional groundwater level information, without localized hydrogeological data. The concept of groundwater level threshold of ecological warning was established according to water development and water re- sources supply, and available groundwater resources were calculated. The concept not only enriches and broadens the content of groundwater studies, but also helps in predicting the prospects for water resources development.
基金supported by the auspices of National Natural Science Foundation of China(No.51079037)Opening Foundation of Chengdu Institute of Plateau Meteorology,China Meteorological Administration(LPM2011002)Natural Science Foundation of Anhui Province(No.1208085ME75)
文摘There are many uncertain factors,such as stochastic,fuzzy and gray information in the risk analysis on natural hazard.The set pair analysis(SPA)deals effectively with the various uncertain factors contributing to evaluation of the risk level of natural disasters.The evaluation indicators and standards of natural disasters risk are analyzed by identity-discrepancycontrary(IDC).The result,the connection numbers,still has uncertainty information.Thus,yielding the risk evaluation model of natural disasters based on connection function,which construct a set pair relation between the indicators of connection numbers and comprehensive evaluation standards,and describe uncertainty of the connection numbers by using connection function.The study showed that the proposed model takes into account only the uncertainty of risk evaluation indicator identification on natural disasters,also the uncertainty of result connection numbers.This approach gives full consideration to the uncertainty of systematic evaluation process along with the actual meaning of comprehensive evaluation functions.Therefore,this means it is able to reduce the uncertainty of final evaluation results and improve the accuracy and reasonability of evaluation results.This model is capable of reflecting actual situation of the risk evaluation on natural disaster affected by various uncertain factors and has a promotional value in the natural disaster risk assessment.
基金funded by the National Natural Science Foundation of China(41904171,42061077)Shanxi Province Education Department Science and Technology Research Plan(18JK0513)+1 种基金State Key Laboratory of Rail Transit Engineering Informatization(FSDI,SKLK19-10)Key Laboratory of ModernEngineering Survey,Natural Science Foundation of Jiangxi Province(20202BAB214029)。
文摘The satellite pseudo-range fault detection with the Receiver Autonomous Integrity Monitoring(RAIM)method is affected by several satellite observations and the geometric distribution of satellites.The poor geometry distribution of satellites will conceal the positioning errorcaused by the satellite pseudo-range fault,resulting in unreliable detection results.Therefore,the availability evaluation must be made before RAIM to ensure that the fault detection performance will not be affected.On June 23,2020,China successfully launched the 30 th(last)navigation satellite of BeiDou’s third-generation navigation satellite system(BDS-3),which is also the 55 th BeiDou navigation satellite.Combining all the available satellites of BDS-1,BDS-2 and BDS-3,the positioning performance of BDS can be greatly improved.In order to evaluate the RAIM availability of BeiDou Navigation Satellite System(BDS)and Global Positioning System(GPS)in China,this paper first deduces the mathematical models and their characteristics of the three RAIM availability evaluation methods.Then,the study area(N10°-70°,E60°-150°)is divided into 4536 grid points at intervals of 1°×1°in latitude and longitude,and the elevations of these grid points are taken from the global terrain data file.The Horizontal Protection Level(HPL)values of these grid points are calculated during 8-15 June 2020 using BDS and GPS ephemeris data.The RAIM availability differences between the two systems are compared and analysed.The analysis shows the Horizontal Protection Level method(HPLM)based on single-satellite pseudo-range fault is the most practical and convenient.During the 8-day observation period,the HPL values of BDS are significantly smaller than those of GPS in terms of geographic location and observation time,and the variation of HPL time series of BDS is also smaller than that of GPS,which indicates that the RAIM availability of GPS in China is not as good as that of BDS.Most importantly,in the four flight stages of the aircraft’s Oceanic/Continental lowdensity En-route,Continental En-route,Terminal En-route and Non-precision approach(NPA),BDS can completely satisfy its RAIM availability requirement,while GPS can only meet the availability requirement of the En-route(Oceanic/Continental low density)phase,and the availability of the other three phases can at least reach 99.714%.
